1. Field of the Invention
This invention is in the field of devices for dampening shaft vibration and noise.
2. Description of the Prior Art
Engine or driven component excited torsionals can result in unacceptable noise and premature torsional fatigue failure of transmissions of drive line components. Viscous type torsional dampers have therefore been developed to attenuate the noise and vibration. I have discussed the development and effects of viscous type dampers in SAE Technical Paper Series 880823. An article entitled "Dealing with Torsional Vibration in Vehicle Drive Lines", published in the April, 1988 publication Diesel Progress North American discusses my efforts to effectively develop solutions to the vibration problem. The prior art includes a number of torsional dampers attachable to a shaft with a torsional damper including an annular housing containing a viscous damper.
In order to increase operating efficiency, the vehicle weight has been decreased resulting in increased torsional fatigue and premature drive line failure. The torsionals are not eliminated by simply increasing the weight and size of drive train components since the torsional stress is simply transferred to the weakest point again resulting in premature failure. As a result, there is a greater need for torsional dampers installed as original equipment as well as retrofit applications on existing shafts.
Torsional dampers are typically mounted to the output shaft of the transmission. The shaft is provided with a flange positionable against one side of the torsional damper with a second flange positioned on the opposite sides of the damper which in turn is attached to the drive shaft. The two flanges are then bolted together "sandwiching" and holding the torsional damper therebetween. In many cases, the adapter flanges are not available particularly for in-field mounting of a torsional damper to an existing vehicle. Further, the drive shaft flanges available are of a variety of configurations which may or may not be accommodated by the selected torsional damper. I have therefore devised an adapter allowing for quick field and or original equipment manufacture installation of a torsional damper. The adapter having a damper mounted thereto may be located at any point along the drive shaft simply by cutting the shaft and inserting the adapter in the cut with the shaft then being welded to the opposite sides of the adapter. The adapter is particularly advantageous in that it provides a means to transfer power from the shaft at a point other than the shaft end.